A healthy young horse starts with a smart vaccination plan. Foals are born with an immature immune system, so the first months are about building protection step-by-step while keeping stress low. Here’s a clear, practical guide you can follow with your veterinarian.
The first 24 hours
Protection begins before the first needle. A foal must drink high-quality colostrum (the mare’s first milk) within six hours of birth. Colostrum delivers vital antibodies that bridge the gap until vaccines can work. Ask your vet to run an IgG test at 12–24 hours to confirm good passive transfer.
- If the mare was not vaccinated pre-foaling, a tetanus antitoxin at birth is often recommended to provide immediate, short-term cover.
Pre-foaling prep for the mare
For future pregnancies, vaccinate the mare 4–6 weeks before foaling with core vaccines. This boosts colostrum quality so the newborn starts life with stronger passive immunity.
Core vaccines foals need
“Core” means life-saving, widely effective and low risk. Your vet may tailor timing to your yard and the dam’s vaccine history, but a common primary series for foals from vaccinated mares is:
- 4–6 months: 1st dose of Tetanus toxoid, EEE/WEE (Eastern & Western equine encephalomyelitis), West Nile virus and Rabies (where licensed).
- 5–7 months: 2nd dose of the same vaccines.
- 6–8 months: 3rd dose of EEE/WEE and West Nile; rabies is usually a single dose; tetanus booster per label.
Foals from unvaccinated mares often start earlier—3–4 months—and still complete a three-dose series four to six weeks apart. Your veterinarian will set the exact schedule.
Risk-based vaccines
Depending on travel, show schedules and yard history, your plan may add:
- Equine influenza and EHV-1/4 (herpes) — common where horses mix or race.
- Strangles — for yards with previous outbreaks.
- Rotavirus — usually given to pregnant mares; foals benefit from the antibodies.
Good practice matters
- Keep vaccines refrigerated and respect the cold chain.
- Use the correct dose, route and site (most are intramuscular; rotate neck/pectoral sites).
- Record every shot (date, lot number, site) and schedule annual boosters.
- Expect mild, short-lived reactions (warmth, stiffness). Call your vet if fever or swelling persists.
Big picture
Vaccines do more than protect one foal—they build herd immunity, lowering the risk for every horse in the barn. Pair your plan with good biosecurity, nutrition and parasite control, and you’ll set your youngster up for a sound, competitive future.
